Nag Aswadhati wrote:
I dont mean that....
Having a primary key table not becomes an IOT?

an IOT might behaves like clustered index in sql server.

No it does not. There is a little similiarity between both. However indexes are constructs mainly used for performance reasons (unique indexes are an exception to that rule). In this regard oracle, sybase and all otehr databases differ greatly. Concepts used on the one database can not be used in similiar way on the other. The reasons why sybase has clustered indexes do not exist in oracle.

See also: http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::p11_question_id:586423377841